The proposed research involves an analysis of the normal development of learning and an examination of the influence of certain environmental factors on the emergence of learning abilities. This study will view temporal and sequential aspects of learning along the full developmental continuum, starting during prenatal stages. For this analysis, a presocial avian species, Anas platyrhynchos (Peking duck) was chosen. Developing capabilities will be evaluated with a number of procedures, including operant learning (escape learning), discriminated avoidance learning, and problem solving. In addition, the influence of differential pre- and postnatal environments (e.g., enrichment, impoverishment) on early behavior and learning will be assessed. Preliminary study by the principal investigator has revealed that the usual environmental enrichment procedures lead to behavioral anomalies (heightened emotionality, hyperactivity), and learning deficits in neonatal ducklings. Therefore, a primary aim of the proposed research will be to study these behavioral anomalies, in order to compare them to certain syndromes found in young humans (particularly hyperkinesis and minimal brain dysfunction). This environmentally induced disruption of normal learning development will be evaluated as a possible model for the study of these problems.